Service Engineering (ICCLab & SPLab)

A Blog of the ZHAW Zurich University of Applied Sciences

Author: benn

Dependability Modeling: Testing Availability from an End User’s Perspective

In a former article we spoke about testing High Availability in OpenStack with the Chaos Monkey. While the Chaos Monkey is a great tool to test what happens if some system components fail, it does not reveal anything about the general strengths and weaknesses of different system architectures. In order to determine if an architecture with 2 redundant controller nodes and 2 compute nodes offers a higher availability level than an architecture with 3 compute nodes and only 1 controller node, a framework for testing different architectures is required. The “Dependability Modeling Framework” seems to be a great opportunity to evaluate different system architectures on their ability to achieve availability levels required by end users.

benn
Kategorie: Articles, OpenStack

The core components of any HA strategy

In his excellent article in Linux Technical Review #04 Jens-Christoph Brendel proposes a new way how to implement High Availability (HA) in current IT architectures. According to Bendel, modern IT architectures continually gain in complexity. This fact makes it difficult to guarantee availability on a certain level. Nevertheless High Availability is not merely a competitional advantage: for many companies keeping availability levels above 99,999 % per year is a matter of existence. Therefore a few systematic steps should help in planning and implementing high availability in your IT environment. This article shows a possible strategy on how to plan High Availability in the Mobile Cloud environment.

benn
Kategorie: Articles, Open Source, OpenStack

High Availability on OpenStack

ICCLab’s MobileCloud Networking solution is supposed to offer private cloud services to end users. MobileCloud is based on OpenStack. Since our OpenStack installation is supposed to be used mainly by end users, it is necessary to provide High Availability.

As mobile end users we all know that we want our IT services to be available everytime and everywhere – 24 hours per day, 7 days per week, 365 days per year. End users normally don’t reflect that this requirement is challenge for system architects, developers and engineers who offer the IT services. Cloud components must be kept under regular maintenance to remain stable and secure. While performing maintenance changes, engineers have to shut down components. At the same time the service should still remain available for the end user. Achieving High Availability in a cloud environment is a very complex and challenging task.

benn
Kategorie: Articles, HowTos, OpenStack